In a vehicle body made of CFRP (Carbon Fiber Reinforced Plastic) of an automobile provided with a floor panel formed by integrating an outer skin and an inner skin with a core interposed therebetween, a side sill, and a front pillar lower, a bracing member corresponding to a corrugated core and made of CFRP or a reinforcing member having a flat plate shape, extending in a front and rear direction, and made of CFRP is disposed inside an upper curved portion in which the front pillar lower stands from a front end of the side sill in order to increase a collapse rigidity of the upper curved portion against a collision load of a front collision. This technique is generally known as disclosed in Japanese Laid-Open Patent Publication No. 2013-252816 and Japanese Laid-Open Patent Publication No. 2014-091423 below.